1. Field of the Invention
The present invention relates to an antenna coil device.
2. Description of the Related Art
In recent years, there has been practically used an electronic key system using an antenna coil device which is installed in a vehicle. In the electronic key system, when a driver who possesses the electronic key enters into the communication zone of the system by coming close to the vehicle, communication is carried out between the antenna coil device and the electronic key, a control circuit on the vehicle side, which is connected to this antenna coil device, is driven, and door unlocking, engine activation and the like are allowed. In addition, when the driver possessing the electronic key comes out from the communication zone of the system by going apart from the vehicle, the control circuit on the vehicle side is driven again and door locking is carried out.
In Patent Document 1 (Japanese unexamined patent publication No. 2009-152784) and Patent Document 2 (Japanese unexamined patent publication No. 2011-205616), there are disclosed antenna coil devices of this kind. For the antenna coil device of the Patent Document 1 (Japanese unexamined patent publication No. 2009-152784), a connector unit and a bobbin are integrally formed and a coil is wound around the cylindrical portion of the bobbin. In the inside of the connector unit, a pair of antenna terminals are exposed. The antenna terminals and the coil are connected through a circuit. The connector unit is interlinked with a connector (vehicle side connector) which is an interface of the control circuit on the vehicle side. In the antenna coil device of the Patent Document 1 (Japanese unexamined patent publication No. 2009-152784), a resin-made case is mounted by being fitted at the periphery of the connector and the bobbin.
Here, the shape and the dimension of the connector on the vehicle side are different generally depending on the type of vehicle. In the antenna coil device of the Patent Document 2 (Japanese unexamined patent publication No. 2011-205616), the terminal board (base unit) provided with the antenna body and the connector unit mounted with the connector on the vehicle side are separately formed by separate members. Thus, the antenna body and the base unit are fabricated by a common component and concurrently, by fabricating the connector unit with an individual shape corresponding to the connector on the vehicle side for everyone thereof, there is achieved generalization for the component of the antenna coil device. In the antenna coil device of the Patent Document 2 (Japanese unexamined patent publication No. 2011-205616), the base unit and the connector unit are indirectly combined integrally by inserting the base unit into one opening of a rubber-made annular elastic plug and by inserting the connector unit into the other opening thereof. The antenna terminal protruding from the base unit is exposed in the inside of the connector unit by passing through an elastic plug. The antenna body and the elastic plug are housed in a case. There are formed protrusions circularly in the periphery of the annular elastic plug and by engaging these protrusions with the inside of the case, the elastic plug, the base unit and the connector unit are to be fixed on the case.